Wastes with Fuel Value
Environmental Engineering · FE Reference Handbook section
Handbook notes for this section
Definitions and conditions exactly as the handbook states them.
- Oily waste and residue 18,000 41,940
Core formulas for this FE topic
Definitions, applicability, units, assumptions and worked examples for each relation.
This section is conceptual; there are no equations to memorise.
Worked exam-style examples
The four ways this section is written on the real exam — thoughts first, then equations, then substitution.
wastes with fuel value heating value estimate for waste-to-energy design Given fraction carbon (C) = 0.4070; fraction hydrogen (H) = 0.0800; fraction oxygen (O) = 0.2980; fraction sulfur (S) = 0.0049, determine the higher heating value of waste (HHV) in MJ/kg.
Given
Find
higher heating value of waste (HHV), in MJ/kg
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except HHV is given, so isolate HHV symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for HHV:
Step 3 — List the givens: fraction carbon (C) = 0.4070, fraction hydrogen (H) = 0.0800, fraction oxygen (O) = 0.2980, fraction sulfur (S) = 0.0049.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning HHV = 24.8429 MJ/kg to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 49.6859 — kept a factor of two that cancels in the correct rearrangement.
- 12.4215 — dropped that same factor in the other direction.
- 27.3272 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
municipal solid wastes with fuel value characterized by elemental analysis Given fraction hydrogen (H) = 0.0380; fraction oxygen (O) = 0.2880; fraction sulfur (S) = 0.0191; higher heating value of waste (HHV) = 14.6800 MJ/kg, determine the fraction carbon (C).
Given
Find
fraction carbon (C)
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except C is given, so isolate C symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for C:
Step 3 — List the givens: fraction hydrogen (H) = 0.0380, fraction oxygen (O) = 0.2880, fraction sulfur (S) = 0.0191, higher heating value of waste (HHV) = 14.6800 MJ/kg.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning C = 0.3099 to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 0.6197 — kept a factor of two that cancels in the correct rearrangement.
- 0.1549 — dropped that same factor in the other direction.
- 0.3409 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value HHV computed from carbon, hydrogen, oxygen, sulfur fractions Given fraction carbon (C) = 0.2110; fraction hydrogen (H) = 0.0990; fraction oxygen (O) = 0.2920; fraction sulfur (S) = 0.0143, determine the higher heating value of waste (HHV) in MJ/kg.
Given
Find
higher heating value of waste (HHV), in MJ/kg
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except HHV is given, so isolate HHV symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for HHV:
Step 3 — List the givens: fraction carbon (C) = 0.2110, fraction hydrogen (H) = 0.0990, fraction oxygen (O) = 0.2920, fraction sulfur (S) = 0.0143.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning HHV = 18.7717 MJ/kg to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 37.5435 — kept a factor of two that cancels in the correct rearrangement.
- 9.3859 — dropped that same factor in the other direction.
- 20.6489 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value heating value estimate for waste-to-energy design Given fraction hydrogen (H) = 0.0450; fraction oxygen (O) = 0.1810; fraction sulfur (S) = 0.0053; higher heating value of waste (HHV) = 5.1300 MJ/kg, determine the fraction carbon (C).
Given
Find
fraction carbon (C)
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except C is given, so isolate C symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for C:
Step 3 — List the givens: fraction hydrogen (H) = 0.0450, fraction oxygen (O) = 0.1810, fraction sulfur (S) = 0.0053, higher heating value of waste (HHV) = 5.1300 MJ/kg.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning C = 0.0408 to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 0.0817 — kept a factor of two that cancels in the correct rearrangement.
- 0.0204 — dropped that same factor in the other direction.
- 0.0449 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
municipal solid wastes with fuel value characterized by elemental analysis Given fraction carbon (C) = 0.2500; fraction hydrogen (H) = 0.0720; fraction oxygen (O) = 0.1690; fraction sulfur (S) = 0.0113, determine the higher heating value of waste (HHV) in MJ/kg.
Given
Find
higher heating value of waste (HHV), in MJ/kg
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except HHV is given, so isolate HHV symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for HHV:
Step 3 — List the givens: fraction carbon (C) = 0.2500, fraction hydrogen (H) = 0.0720, fraction oxygen (O) = 0.1690, fraction sulfur (S) = 0.0113.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning HHV = 18.8661 MJ/kg to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 37.7323 — kept a factor of two that cancels in the correct rearrangement.
- 9.4331 — dropped that same factor in the other direction.
- 20.7528 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value HHV computed from carbon, hydrogen, oxygen, sulfur fractions Given fraction hydrogen (H) = 0.0820; fraction oxygen (O) = 0.1820; fraction sulfur (S) = 0.0099; higher heating value of waste (HHV) = 13.0400 MJ/kg, determine the fraction carbon (C).
Given
Find
fraction carbon (C)
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except C is given, so isolate C symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for C:
Step 3 — List the givens: fraction hydrogen (H) = 0.0820, fraction oxygen (O) = 0.1820, fraction sulfur (S) = 0.0099, higher heating value of waste (HHV) = 13.0400 MJ/kg.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning C = 0.0971 to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 0.1942 — kept a factor of two that cancels in the correct rearrangement.
- 0.0486 — dropped that same factor in the other direction.
- 0.1068 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value heating value estimate for waste-to-energy design Given fraction carbon (C) = 0.4020; fraction hydrogen (H) = 0.0270; fraction oxygen (O) = 0.2260; fraction sulfur (S) = 0.0098, determine the higher heating value of waste (HHV) in MJ/kg.
Given
Find
higher heating value of waste (HHV), in MJ/kg
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except HHV is given, so isolate HHV symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for HHV:
Step 3 — List the givens: fraction carbon (C) = 0.4020, fraction hydrogen (H) = 0.0270, fraction oxygen (O) = 0.2260, fraction sulfur (S) = 0.0098.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning HHV = 18.3527 MJ/kg to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 36.7054 — kept a factor of two that cancels in the correct rearrangement.
- 9.1763 — dropped that same factor in the other direction.
- 20.1880 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
municipal solid wastes with fuel value characterized by elemental analysis Given fraction hydrogen (H) = 0.0720; fraction oxygen (O) = 0.3400; fraction sulfur (S) = 0.0045; higher heating value of waste (HHV) = 17.2000 MJ/kg, determine the fraction carbon (C).
Given
Find
fraction carbon (C)
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except C is given, so isolate C symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for C:
Step 3 — List the givens: fraction hydrogen (H) = 0.0720, fraction oxygen (O) = 0.3400, fraction sulfur (S) = 0.0045, higher heating value of waste (HHV) = 17.2000 MJ/kg.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning C = 0.2819 to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 0.5637 — kept a factor of two that cancels in the correct rearrangement.
- 0.1409 — dropped that same factor in the other direction.
- 0.3101 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value HHV computed from carbon, hydrogen, oxygen, sulfur fractions Given fraction carbon (C) = 0.4310; fraction hydrogen (H) = 0.0210; fraction oxygen (O) = 0.2840; fraction sulfur (S) = 0.0063, determine the higher heating value of waste (HHV) in MJ/kg.
Given
Find
higher heating value of waste (HHV), in MJ/kg
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except HHV is given, so isolate HHV symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for HHV:
Step 3 — List the givens: fraction carbon (C) = 0.4310, fraction hydrogen (H) = 0.0210, fraction oxygen (O) = 0.2840, fraction sulfur (S) = 0.0063.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning HHV = 17.7508 MJ/kg to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 35.5015 — kept a factor of two that cancels in the correct rearrangement.
- 8.8754 — dropped that same factor in the other direction.
- 19.5258 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)
wastes with fuel value heating value estimate for waste-to-energy design Given fraction hydrogen (H) = 0.0930; fraction oxygen (O) = 0.3040; fraction sulfur (S) = 0.0043; higher heating value of waste (HHV) = 32.4200 MJ/kg, determine the fraction carbon (C).
Given
Find
fraction carbon (C)
Start with the thinking
- The governing relation printed in this handbook section is Wastes with Fuel Value.
- Everything except C is given, so isolate C symbolically first — never rearrange after the numbers are in.
- Tabulate each given with its unit and confirm the units are consistent with the relation before substituting.
- Wastes with fuel value are characterized by a Dulong-type formula estimating higher heating value from elemental composition.
Step-by-step solution
Step 1 — State the governing relation:
Step 2 — Rearrange symbolically for C:
Step 3 — List the givens: fraction hydrogen (H) = 0.0930, fraction oxygen (O) = 0.3040, fraction sulfur (S) = 0.0043, higher heating value of waste (HHV) = 32.4200 MJ/kg.
Step 4 — Substitute the given values:
Step 5 — Evaluate:
Step 6 — Check: returning C = 0.5340 to
reproduces the given quantities, and both sides carry the same units.
Why the other options are there
- 1.0681 — kept a factor of two that cancels in the correct rearrangement.
- 0.2670 — dropped that same factor in the other direction.
- 0.5874 — rounded an intermediate value before the final step.
Reference: FE Handbook — Wastes with Fuel Value (Dulong formula)